The MM300 multimeter measuresAC/DC voltage, DC current and resistance and has a safety rating of CAT III 600V, Class 2, Double insulation. The NCVT-1 has a bright green LED to indicate the tester is working. It changes to red and warning tones sound when voltage is detected. NCVT-1 has a digitally-controlled ON/OFF power button and auto power-off feature to conserve and extend battery life.